parse                  package:base                  R Documentation

_P_a_r_s_e _E_x_p_r_e_s_s_i_o_n_s

_D_e_s_c_r_i_p_t_i_o_n:

     'parse' returns the parsed but unevaluated expressions in a list. 
     Each element of the list is of mode 'expression'.

_U_s_a_g_e:

     parse(file = "", n = NULL, text = NULL, prompt = "?")

_A_r_g_u_m_e_n_t_s:

    file: a connection, or a character string giving the name of a file
          or a URL to read the expressions from. If 'file' is '""' and
          'text' is missing or 'NULL' then input is taken from the
          console.

       n: the number of statements to parse.  If 'n' is negative the
          file is parsed in its entirety.

    text: character vector. The text to parse. Elements are treated as
          if they were lines of a file.

  prompt: the prompt to print when parsing from the keyboard. 'NULL'
          means to use R's prompt, 'getOption("prompt")'.

     'NULL' means to use R's prompt, 'getOption("prompt")'.

_D_e_t_a_i_l_s:

     All versions of R accept input from a connection with end of line
     marked by LF (as used on Unix), CRLF (as used on DOS/Windows) or
     CR (as used on classic MacOS).  The final line can be incomplete,
     that is missing the final EOL marker.

     See 'source' for the limits on the size of functions that can be
     parsed (by default).

_R_e_f_e_r_e_n_c_e_s:

     Becker, R. A., Chambers, J. M. and Wilks, A. R. (1988) _The New S
     Language_. Wadsworth & Brooks/Cole.

_S_e_e _A_l_s_o:

     'scan', 'source', 'eval', 'deparse'.

_E_x_a_m_p_l_e_s:

     cat("x <- c(1,4)\n  x ^ 3 -10 ; outer(1:7,5:9)\n", file="xyz.Rdmped")
     # parse 3 statements from the file "xyz.Rdmped"
     parse(file = "xyz.Rdmped", n = 3)
     unlink("xyz.Rdmped")

